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81.
B L Strehler 《Synapse (New York, N.Y.)》1991,7(1):44-91
The enigmatic nature of the experience of self-awareness is examined in the light of recent discoveries and, on this basis, combined with inferences derived introspectively from the experience of the phenomenon itself; a specific physical locus of this experience within the human brains is deduced-proposed. The fundamental premise in this work is that whereever conscious self-awareness is generated, the neuronal structure(s) involved must continually have access to an extremely precise representation of information derived from the sense of vision plus a great variety of other kinds of information so as to permit it to make decisions regarding actions (movements and their implementation) that promote the survival and perpetuation of the biological system in which the self is generated. First, a definitve set of criteria that define most of the inputs to and operations carried out by the self-awareness entity were assembled. This ensemble of functions was then compared with the connections and possible roles of specific neuroanatomical structures described in published literature, particularly the recent literature and particularly that concerned with the sense of vision. It was discovered that only one brain structure receives the prerequisite information from the sense of vision plus information derived from cortical memory stores plus a variety of other relevant sources needed to generate a coherent sense of selfness. This structure is the superior colliculus of the tectum. The superior colliculi not only receive a highly precise retinotopic representation of inputs to the eyes, but also receive inputs from a great variety of other structures, including many areas of the cerebral cortex, vestibular inputs, auditory inputs, "affective" inputs, and inputs that putatively define the positions of the eyes and of the head. This information, it is deduced, not only allows this structure to generate a continuing synthesis of representations of the self-vs.-environment, but also allows a part of it to assess the significance (probable meaning) of these integrated inputs with respect to the selection of an implementation of actions that serve the interests of the physical structure in which the self-experience is generated. The function of memory in this system not only involves the continually updated representation of where the self is with respect to items and objects in its environment, but also provides means through which the relevance of recorded experiences representing the past may be caused to affect the decision-making process.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
82.
Edmund Przegaliński Leokadia Baran Władysław Palider Joanna Siwanowicz 《Psychopharmacology》1979,62(3):295-300
The central action of the potential antidepressant drug pizotifen (Sandomigran) was studied in mice, rats and rabbits. Pizotifen in doses up to 10 mg/kg i.p. was ineffective in classic tests for antidepressant activity. It neither antagonized the effects of reserpine in rats (hypothermia, ptosis) nor potentiated the effects of amphetamine (in mice and rats), nialamide or L-dopa (in mice) on locomotor activity. However, its antidepressant activity was found in the despair test in rats.On the other hand, pizotifen inhibited the head twitch reaction induced by L-5-hydroxytryptophan in mice (ED50=0.009 mg/kg, i.p.) and by 5-methoxytryptamine (+tranylcypromine) in rats (ED50=0.45 mg/kg, i.p.). It also antagonized tryptamine-induced clonic convulsions of fore-paws in rats (ED50=0.35 mg/kg, i.p.), and in doses of 5–10 mg/kg s.c. inhibited hyperthermia produced by LSD in rabbits. Finally, pizotifen (0.1–0.3 mg/kg, i.v.) inhibited or abolished LSD- or quipazine-induced stimulation of the hind limb flexor reflex of spinal rats; the above effect was not due to noradrenolytic action of the drug. These results suggest that pizotifen strongly blocks the central postsynaptic serotonin receptors. 相似文献
83.
84.
鹿茸口服液促进RNA和蛋白质合成作用的研究 总被引:1,自引:0,他引:1
目的:研究鹿茸口服液对青年及老年小鼠RNA和蛋白质合成的作用。方法:观察口服鹿茸口服液对小鼠肝RNA和蛋白质含量及^3H-Uridine和^3H-Leucine掺入的影响。结果:鹿茸口服液可明显增加老年小鼠肝RNA和蛋白质含量及[^3H]Uridine和[^3H]Leucine掺入RNA和蛋白质,作用明显强于青年小鼠。结论:鹿茸口服液对老年小鼠RNA和蛋白质合成有明显促进作用。 相似文献
85.
86.
Selective cyclo-oxygenase-2(COX-2) inhibitor, VI-OXX(rofecoxib), was voluntarily withdrawn worldwide from drugstores by its maker Merck & Co., Inc. on Sep-tember 30, 2004, for its potential lethal side effects of heart attack or stroke. 相似文献
87.
In the present paper, the authors review some major effects of acupuncture in the treatment of clinical diseases and sum up some results of experimental researches on the mechanisms of acupuncture. Up to now, clinical practice and experimental researches demonstrate that acupuncture possesses good analgesic effect, integrative regulation effect on the functional activities of the body and 相似文献
88.
In the present paper, the author makes some comments on the holistic action of acupuncture from the regulative effect on the nerve-endocrine-immune network, and the close relationship between the nerve-endocrineimmune network and the meridian-collateral system of TOM. The wholism concept of TOM refers to the organism being an integrated entirety, and the regulatory effect of acupuncture on functional activities of the organism relies on the integral connection of the acupoint--meridian-collateral-zangfu-organ system. When stimulated with acupuncture, the human body will brings its potential force into full play in preventing and treating diseases. 相似文献
89.
目的 探讨银环蛇毒素及其若干组分在体外对白血病K562细胞株的凋亡诱导作用。方法 采用阳离子交换层析法分离纯化银环蛇粗毒,应用MTT法、荧光显微镜和流式细胞术等研究毒素对K562细胞株的凋亡作用。结果 除Ⅳ峰毒素外,银环蛇粗毒及分离的部分组分IV峰、Ⅶ峰和Ⅷ峰等毒素的荧光显微图末见特征性的凋亡小体,DNA含量分布组方图中的二倍体峰前末见Gl细胞群。结论 银环蛇毒对K562细胞具有杀伤作用,但并非是细胞凋亡作用,而是致细胞坏死,而粗毒中的某些组分可能具有促K562细胞凋亡作用。 相似文献
90.
6名健康妇女分别于上臂、臀部和腹部三部位经皮给予合LNG的透皮控释传递系统(TCDS)后,用放射免疫法测定LNG血清浓度,计算其主要药物动力学参数。结果表明:在TCDS用药期间,三部位的C(max)、T(max)及AUC(0~168h)基本接近,部位间无显著性差异(P>0.05);TCDS揭除后,AUC(168~204h)及消除相半衰期T(1/2)(Ke)均以腹部最大,臀部次之,上臂最小,在腹部与上臂间有显著性差异(P<0.05)。上述结果可归因于TCDS对LNG的控释和人体皮下脂肪的“贮库效应”。 相似文献